In general, a heat sink is metallic device that conveys heat from one or more circuit board components (e.g., high speed processors, Field Programmable Gate Arrays, optical transceivers, etc.) into the surrounding air. An air stream generated by a fan assembly then carries the heat away. Such operation enables the circuit board components to operate in a lower temperature range without increasing the likelihood of operating incorrectly and/or sustaining damage.
There are a variety of approaches for a circuit board manufacturer (or supplier) to mount a heat sink to a circuit board component. One conventional approach (hereinafter referred to as the “conventional standoff approach”) involves the manufacturer providing mounting holes in circuit board locations surrounding the circuit board component. Under this approach, the manufacturer then installs standoffs (i.e., threaded metallic posts, nuts, and perhaps other loose hardware) on the circuit board through the mounting holes, and places the heat sink over the top of the component, perhaps with thermal transfer material disposed between the top of the component package and the heat sink to facilitate heat transfer therebetween. Next, the manufacturer rigidly secures the heat sink to the standoffs. As a result, when the component is in operation, the heat sink, which is held rigidly in place by the standoffs, conducts heat from the component and dissipates that heat into a neighboring air stream.
Another conventional approach for mounting a heat sink to a circuit board component (hereinafter referred to as the “conventional adhesive approach”) involves the manufacturer essentially affixing the heat sink directly to the component package using an adhesive (e.g., tape, glue, combinations thereof, etc.) having a high thermal transfer coefficient. In this approach, the manufacturer applies a pressure sensitive adhesive (PSA) between the circuit board component and the heat sink. The manufacturer then applies pressure to between the component and the heat sink to secure them together. For some adhesives, the manufacturer further applies heat to cure glue-like material within the adhesive and thus more-rigidly secure the heat sink to the component. Accordingly, when the component is in operation, the heat sink, which is held firmly in place by the adhesive, dissipates heat from the component into the surrounding air.